diff --git a/c/masync_server/Makefile b/c/masync_server/Makefile
index 38892c2..f34992a 100644
--- a/c/masync_server/Makefile
+++ b/c/masync_server/Makefile
@@ -5,7 +5,7 @@ OBJECTS=$(SOURCES:%.c=%.o)
 #CFLAGS=-march=core2 -mtune=core2 -O2 -mfpmath=sse -msse4.1 -pipe
 #LDFLAGS=-Wl,-O1 -Wl,--as-needed
 
-CFLAGS+=-O2 $(shell pkg-config --cflags liblist)
+CFLAGS+=-g $(shell pkg-config --cflags liblist)
 LDFLAGS+=$(shell pkg-config --libs liblist) -lpthread
 
 all: $(TARGET) echo-server echo-client